Water at a mean temperature of 80 °C and a mean velocity of 0.15 m/s flows...

Water at a mean temperature of 80 °C and a mean velocity of 0.15 m/s flows inside a 2.5 cm ID and 3.3 cm OD, copper tube. Atmospheric air at 20 °C and a velocity of 10 m/s flows across the tube. Calculate the overall heat transfer coefficient based on the outer surface and the rate of heat loss per 1 m length of the tube for inside and outside fouling factor 0.00018 m2. What is the percent reduction in the overall heat transfer coefficient due to the dirty conditions in the heat exchanger? (Assume that the value the waterside heat transfer coefficient is 250 W/m2.°C and that of the airside is 75 W/m2.°C.

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samet mamat answered 2 years ago

Water at a temperature of 80 °C and velocity of 1.2 m/s is flowing parallel to...

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